1. Field of the Invention
The present invention relates to a magnet cover caulking method of an electric motor which is preferably used in a motor-driven power steering apparatus or the like.
2. Description of the Related Art
In an electric motor used in a motor-driven power steering apparatus or the like as described in Japanese Patent Application Laid-Open No. 2007-1364 (patent document 1), a magnet is positioned and retained by providing the magnet in an outer periphery of a rotating shaft and providing a magnet holder in both end sides of the magnet in the outer periphery of the rotating shaft. A magnet cover is installed to an outer periphery of the magnet and the magnet holder so as to be fixed, thereby covering the magnet.
In the conventional electric motor, as a fixing method of the magnet cover, an end portion of the magnet cover installed to the outer periphery of the magnet and the magnet holder is roll caulked perpendicularly. Complicated roll caulking equipment is necessary and caulking time is long.